Indulgences were sold to help the church make money. They were official pardons given by the pope to excuse sins that people have committed so they could have a place in heaven. People would pay the church money to recieve them. One particular person that stands out when you talk about indulgences is Martin Luther, who believed that you do not need and indulgenges to get into heaven, if you lived a good life you be accepted. The person who started Indulgences was Johann Tetzel. He used the money from indulgences to rebuild St. Peter's. You could even have Indulgences for the sins you haven't done yet.